The invention relates to medical diagnostic instruments and more particularly to a telescoping compact retinoscope which can easily be stored in a jacket or coat pocket, or pocket carrying case.
Conventional prior art retinoscopes normally have a nominal length of about 10 inches including the head and handle portion. This typical size makes the instrument inconvenient and unsuitable for storage and carrying in a coat or jacket pocket. It therefore requires that the instrument be stored and secured in a larger carrying case for transport when the doctor is using the retinoscope outside of his office such as conducting visits to clinics, nursing homes, and the like.
There is, therefore, a need in the field for a compact retinoscope which is significantly smaller in size than retinoscopes of the prior art, and which can be easily contained or stored in a pocket or pocket carrying case with a portable power source. In the medical field portable power sources are currently used to power and store other medical and diagnostic instruments such as ophthalmoscopes and retinoscopes. Portable powers of this type are currently being sold by Welch Allyn, Inc. of Skaneateles Falls, N.Y., under the trademark CompacSet.TM. and Pocketscopes.TM..
Accordingly, it is an object of the present invention to provide a compact retinoscope having telescoping features which may be conveniently accommodated or stored in a pocket or pocket carrying case, and which overcomes the disadvantages noted above. U.S. Pat. Nos. 5,189,449; 5,200,772; and 5,202,710 are representative of conventional retinoscopes of the prior art, having a size of approximately 4.5 inches in total length.
The minimum length required for the retinoscope of the present invention is at odds with need for the required optical length to provide the optical performance of full size retinoscopes, and therefore presented the need for a telescoping mechanism to accomplish the objectives of the invention.